Yaxe:It was no uncommon for a coded message to have a number of layers of encryption. The acronyms mean something, but that meaning may be lost to time.

No. Those aren't acronyms. This guy is in essence "making shiat up", inventing acronyms to fit what he thinks are the message.

As for coded messages having a number of layers of encryption, this is a field cipher, made to be done simply using paper and pencil by a person of relatively average intelligence. Because it is being transmitted through a relatively secure means (carrier pigeon) and because it wouldn't likely carry identifying information, and the information is probably of limited time sensitivity (if you are arranging a supply drop for June 30th, if the Germans manage to break it on July 1st, it doesn't do them much good), you wouldn't have layers of encryption.

The normal field cipher for SOE at the time was a double transposition cipher, or perhaps a one time pad. If it's a double transposition, which seems unlikely given the high incidence of Q and X unless they were used as word separators or periods. Might be an OTP, in which case it will remain undeciphered forever, or if it is double transposition, it may have been enciphered monoalphabetically at first (which the frequency count does kind of suggest).

dittybopper:Yaxe: It was no uncommon for a coded message to have a number of layers of encryption. The acronyms mean something, but that meaning may be lost to time.

No. Those aren't acronyms. This guy is in essence "making shiat up", inventing acronyms to fit what he thinks are the message.

As for coded messages having a number of layers of encryption, this is a field cipher, made to be done simply using paper and pencil by a person of relatively average intelligence. Because it is being transmitted through a relatively secure means (carrier pigeon) and because it wouldn't likely carry identifying information, and the information is probably of limited time sensitivity (if you are arranging a supply drop for June 30th, if the Germans manage to break it on July 1st, it doesn't do them much good), you wouldn't have layers of encryption.

The normal field cipher for SOE at the time was a double transposition cipher, or perhaps a one time pad. If it's a double transposition, which seems unlikely given the high incidence of Q and X unless they were used as word separators or periods. Might be an OTP, in which case it will remain undeciphered forever, or if it is double transposition, it may have been enciphered monoalphabetically at first (which the frequency count does kind of suggest).

I think you've likely got a much better grasp of this than I do, but my first thought was this seems like it was probably done using a one time pad and this will remain one of those cool, unsolved and ultimatly unsolveable mysterys.

I like that this guy approached the problem from a different angle and all, but shoehorning five letter acronyms into this really doesn't seem to add up. If each segment was of variable length I might be inclined to believe it a bit more.

error 303:dittybopper: Yaxe: It was no uncommon for a coded message to have a number of layers of encryption. The acronyms mean something, but that meaning may be lost to time.

No. Those aren't acronyms. This guy is in essence "making shiat up", inventing acronyms to fit what he thinks are the message.

As for coded messages having a number of layers of encryption, this is a field cipher, made to be done simply using paper and pencil by a person of relatively average intelligence. Because it is being transmitted through a relatively secure means (carrier pigeon) and because it wouldn't likely carry identifying information, and the information is probably of limited time sensitivity (if you are arranging a supply drop for June 30th, if the Germans manage to break it on July 1st, it doesn't do them much good), you wouldn't have layers of encryption.

The normal field cipher for SOE at the time was a double transposition cipher, or perhaps a one time pad. If it's a double transposition, which seems unlikely given the high incidence of Q and X unless they were used as word separators or periods. Might be an OTP, in which case it will remain undeciphered forever, or if it is double transposition, it may have been enciphered monoalphabetically at first (which the frequency count does kind of suggest).

I think you've likely got a much better grasp of this than I do, but my first thought was this seems like it was probably done using a one time pad and this will remain one of those cool, unsolved and ultimatly unsolveable mysterys.

I like that this guy approached the problem from a different angle and all, but shoehorning five letter acronyms into this really doesn't seem to add up. If each segment was of variable length I might be inclined to believe it a bit more.

I would guess one-time pad myself, for the reasons you give. The message has to be field encoded by someone with average mathematical abilities, transmitted via pigeon, then decoded and transmitted to it's destination with enough time to act on the info. Given that it's a pigeon message, it's probably tactical data. And if the guy's theory is correct, and the pigeon releaser was giving positions of German units for artillery support, some of those letters would have to represent numbers on a map grid.

error 303:I think you've likely got a much better grasp of this than I do, but my first thought was this seems like it was probably done using a one time pad and this will remain one of those cool, unsolved and ultimatly unsolveable mysterys.

I'm a little skeptical of it being a one time pad. I've experimented with them myself (google "one time pad dittybopper"), and in fact came up with what I think was a unique way to generate numeric one time pads manually, through the use of 10-sided dice: I googled it, and asked a few of my SIGINT buddies, and no one had heard of the idea before.

Anyway, when I did a frequency count, it looked a lot like the normal frequency distribution of an English message. With such a short message, though, it's possible that an OTP might cause that.

One caution: The AOAKN group is an indicator of some kind, shown by it's repetition at the end of the message, and it shouldn't be included in the frequency count.

dittybopper:Yaxe: It was no uncommon for a coded message to have a number of layers of encryption. The acronyms mean something, but that meaning may be lost to time.

No. Those aren't acronyms. This guy is in essence "making shiat up", inventing acronyms to fit what he thinks are the message.

As for coded messages having a number of layers of encryption, this is a field cipher, made to be done simply using paper and pencil by a person of relatively average intelligence. Because it is being transmitted through a relatively secure means (carrier pigeon) and because it wouldn't likely carry identifying information, and the information is probably of limited time sensitivity (if you are arranging a supply drop for June 30th, if the Germans manage to break it on July 1st, it doesn't do them much good), you wouldn't have layers of encryption.

The normal field cipher for SOE at the time was a double transposition cipher, or perhaps a one time pad. If it's a double transposition, which seems unlikely given the high incidence of Q and X unless they were used as word separators or periods. Might be an OTP, in which case it will remain undeciphered forever, or if it is double transposition, it may have been enciphered monoalphabetically at first (which the frequency count does kind of suggest).

cgraves67:I would guess one-time pad myself, for the reasons you give. The message has to be field encoded by someone with average mathematical abilities, transmitted via pigeon, then decoded and transmitted to it's destination with enough time to act on the info. Given that it's a pigeon message, it's probably tactical data. And if the guy's theory is correct, and the pigeon releaser was giving positions of German units for artillery support, some of those letters would have to represent numbers on a map grid.

Double transposition is easy enough. It has the advantage of having the key be memorable, so nothing needs to be written down.

The problem with one time pad use is having enough key material. A message that length would require a key the same length. This is compounded by the fact that for SOE use, they were printed on silk, which prevents the print from being below a certain size, and it also complicates the destruction as silk doesn't burn as easily as paper.

When you are making paper pads, you can print them pretty much arbitrarily small, down to the limit of unaided human vision. Normally, though, I find that by using thin paper, a manual typewriter, and keeping the size of the pad reasonably small, you can make pads that you can hide pretty much anywhere. Certainly, a pad useful for messages this length would have been small enough to hide in almost any object: Sole of a shoe, a collar or cuff, barrel of a pen, hat brim, etc.

Were one time pads that widespread in WWII? My understanding (which may be completely off) is that they really only became widely used when there were computers to help. Generating and distributing truly unique pads for every spotter in Europe by hand seems extremely cumbersome.

dittybopper:error 303: I think you've likely got a much better grasp of this than I do, but my first thought was this seems like it was probably done using a one time pad and this will remain one of those cool, unsolved and ultimatly unsolveable mysterys.

I'm a little skeptical of it being a one time pad. I've experimented with them myself (google "one time pad dittybopper"), and in fact came up with what I think was a unique way to generate numeric one time pads manually, through the use of 10-sided dice: I googled it, and asked a few of my SIGINT buddies, and no one had heard of the idea before.

Anyway, when I did a frequency count, it looked a lot like the normal frequency distribution of an English message. With such a short message, though, it's possible that an OTP might cause that.

One caution: The AOAKN group is an indicator of some kind, shown by it's repetition at the end of the message, and it shouldn't be included in the frequency count.

Given the message structure and the location of the indicator it seems reasonable, and without knowing the origin text I'd think it basically impossible to ever crack. Does that seem reasonable? I really know next to nothing about this sort of thing.

ArkPanda:Were one time pads that widespread in WWII? My understanding (which may be completely off) is that they really only became widely used when there were computers to help. Generating and distributing truly unique pads for every spotter in Europe by hand seems extremely cumbersome.

It is cumbersome, but perhaps not as cumbersome as you might think. Tedious, perhaps, is a better word. When you get into a rhythm, you can generate them fairly quickly. I imagine that you could hire a number of typists to generate them using some sort of hardware random number generator, perhaps 10-sided dice for numeric pads, or something like a bag of Scrabble tiles for alphabetic ones. I've done that with the dice for numeric pads, and you can make those relatively quickly:

However, because they are unbreakable*, they are precisely the kind of thing you want to equip your field agents with, and that is why they are still used to this very day. You know those shortwave number stations? They are precisely that: Communications to agents in the field using one time pads. The low information rate, and the necessity of absolute security, means there will always be a place for them.

*When used properly, of course. The Soviets made the mistake of re-using some pads during WWII. That allowed us to break some small fraction of the messages they sent using them. See: The Venona Project.

error 303:I guess this is more along the lines of what I was thinking maybe :

Running Key Cipher

Given the message structure and the location of the indicator it seems reasonable, and without knowing the origin text I'd think it basically impossible to ever crack. Does that seem reasonable? I really know next to nothing about this sort of thing.

Read your link:

if (as usual) the running key is a block of text in a natural language, security actually becomes fairly poor, since that text will have non-random characteristics which can be used to aid cryptanalysis. As a result, the entropy per character of both plaintext and running key is low, and the combining operation is easily inverted.

Well, we know the SOE used double transposition, based at first on published poems, then based upon non-published ones, and finally shifting over to one time pads, so a running key cipher that isn't an OTP seems to be excluded.

Aha, so those military records I added to my family tree aren't just mispelling "Sergeant" as "Serjeant", that's the way they spelled "Sergeant" in those regiments.

I wondered why an officer would spell so badly. Yes, some of them were upper class twits perhaps, but their handwriting wasn't bad and spelling was pretty much standardized by that time so that random spellings indicated illiteracy.

Wery interestink. English spelling lays engines and snares before the feet of the unwary and the foreigner.